/**
 *This shader will render a billboard as a 2D billboard.
 *It will assume the world matrix contain screen-space transformations. 
 **/

uniform mat4 worldMat;
uniform mat4 projMat;
uniform mat4 viewMat;
uniform mat4 wvpMat;

attribute vec4 vertex;
attribute vec4 uv0;

void main(void)
{
  //gl_Position = projMat * (worldMat[3] + vertex);
  gl_Position = wvpMat * vertex;
  gl_TexCoord[0] = uv0;
}
